The most common freelance pricing mistake isn't charging too much. It's charging a salary-equivalent rate without accounting for everything that's now your problem.
New freelancers often look at their last salary ($75,000) and price at the hourly equivalent ($36/hr). The problem: that salary came with health insurance, paid vacation, an employer-paid FICA contribution, and 100% of your time being billable. As a freelancer, none of that applies.
As a freelancer, you pay both the employee and employer portions of Social Security and Medicare (15.3% combined), plus income tax. Many freelancers are surprised to find their effective tax rate is 30-40% when they first calculate it properly.
Admin, invoicing, sales, proposal writing, client emails — these are real work hours that don't appear on any invoice. 35-40% of a freelancer's total working time is typically unbillable. If you price assuming 100% billability, you're working those hours for free.
Health insurance ($5,000-10,000/year for a decent individual plan), retirement contributions, paid time off that costs you revenue — these were invisible in a salary. As a freelancer, they're explicit costs that need to be in your rate.